Alternatives: McClellan

[Saphroneth]

I though I should make sure that we're all on the same page regarding troop positions - @67th Tigers , I'd appreciate a quick look-over of this map to ensure I've got it right (I probably haven't).

Am I correct in my understanding that this is the position of the Union divisional main strength as of just before the historical Seven Pines, and that the yellow markers indicate all the functioning bridges?

 

[1SGDan]

For example, you list a 27th May wooden bridge at New Bridge. This did not exist. The detachment tasked with building this bridge reported their progress to the 29th:

A direct quote from page 13 The Engineer Battalion in the Civil War, by Gilbert Thompson, a private and a corporal in the Battalion during the Civil War, later a major in in the Corps of Engineers

"May 27, at 4a.m. Companies A and C marched to New Bridge, and threw a ponton bridge, afterwards taken up, as the enemy's pickets made an advance."

Since he was there and we were not I am compelled to believe him. These are the regular engineers not to be confused with the Engineer Brigade comprised of the 50th and 15th New York Engineers.

 

[67th Tigers]

Since he was there and we were not I am compelled to believe him. These are the regular engineers not to be confused with the Engineer Brigade comprised of the 50th and 15th New York Engineers.

Indeed. I do believe him in his statement that they failed to get a bridge over the Chickahominy in time to be of use.

Mission failure for the engineers.

Unfortunately they also failed in their orders to save the pontoons at New Bridge on 26th June, leading to the army being stuck north of the James. Worse, they failed to properly destroy the pontoon bridges, and the pontoons were refloated and Longstreet's division was able to cross the Chickahominy there on the 28th. The destruction of the Grapevine bridge was more extensive, taking until late on the 29th to repair. Lee's orders were for Longstreet and AP Hill to cross at New Bridge (which there did on the 28th) and Jackson and DH Hill to cross at the Grapevine Bridge (which was done 29th-30th). Had the engineers been a little more thorough at New Bridge then probably the Glendale position could have been maintained.

 

[1SGDan]

Actually it confirms what CW3O has been postulating. Failure to secure the far side of the river made it impossible to build and maintain a bridge near New Bridge. The bridge in question here was removed due to the threat of enemy forces. This situation kept the two wings of the army split.

 

[Saphroneth]

Actually it confirms what CW3O has been postulating. Failure to secure the far side of the river made it impossible to build and maintain a bridge near New Bridge.

But as has been noted the far side of the river was under Union control for about a week. How long do you need?

If Sumner had been committed to hold the heights in main force then it would have been possible to hold the heights over New Bridge, but at the cost of an attack at Beaver Dam Creek being an enormous risk - by my count an attack at BDC on the 31st would have left the closest disposable forces (to whit, Kearny, if he's not needed also in the now-extended line) is 15 miles or a full day's march away, while Sumner's forces would have about 10-11 miles to go. Essentially it's a gamble that (1) the attack will happen on the south side of the river not the north and (2) the divisional frontage employed by e.g. Casey's division before Seven Pines is adequate to hold without any real prospect of reinforcement, as the reserves are cut pretty drastically.

This situation kept the two wings of the army split.

And New Bridge, meanwhile, doesn't actually solve anything. Holding the heights over New Bridge and New Bridge being operational changes nothing about the required deployments as of 25 June except that the Federal line is the Federal line as of 26-27 June instead. Having New Bridge doesn't remove the problem of being split either side of the Chickahominy, after all, and historically the problem with moving troops to meet Lee's attack was largely caused by Porter initially deciding he didn't need help...

 

[1SGDan]

What has been shown is that you actually are unwilling to accept any of the alternatives you asked for. Mac butt scrubbing 150+ years later doesn' t absolve him from leading a failed campaign.

 

[Saphroneth]

What has been shown is that you actually are unwilling to accept any of the alternatives you asked for. Mac butt scrubbing 150+ years later doesn' t absolve him from leading a failed campaign.

Au contraire. There are already a number of possible alternative approaches that I have accepted as plausible - I just don't think they're clearly superior, in most cases.

- Pushing the main line of resistance forwards to the New Bridge Heights with Sumner.
Essentially, this is a calculated risk that may well have paid off - but it is a risk, taken when the enemy's force in the area is at least comparable (with Porter elsewhere). It does not resolve the "split both sides of the Chickahominy" problem and the northern flank is still vulnerable to the Seven Days attack.
It is also an unjustified risk at the time unless McClellan knows both that 1st Corps is not actually coming and that the rains will prevent offensive action for a month - if 1st Corps is coming and offensive action will be possible in the bulk of June, then an advance on a seven-division line (2nd, 3rd, half 4th, 6th) south of the Chickahominy with 1st and 5th north is clearly superior.
Thus, this alternative is plausible (it doesn't require an assault on nearly equal numbers dug in in a mile-deep fortification line, say), but contains tradeoffs.

- Using both 5th and 6th corps north of the Chickahominy before the opening of the Seven Days.
This is the opposite to the advanced MLR, it's taking a fully defensive stance. It means no Seven Days, but it also means no attack on Richmond.

- Waiting an extra day to attack at Antietam on the 18th, after having just taken the lower bridge on the 17th.
This would mean that 1st, 2nd, 12th and 6th could make a coordinated attack in the north with full ammunition supply, or that 6th could reinforce the southern flank now that the bridge has been taken. It means waiting until more of McClellan's army is 'up' and stragglers have come in.
This achieves better force concentration than the historical attack, and if McClellan had known Lee's army had managed to largely reunite I suspect he would have taken it.

- Sending Franklin along the south bank of the Potomac on the 17th after AP Hill left.
This would have offered a strong chance for the destruction of the Army of Northern Virginia, assuming that the attacks in the north were pressed less strongly so as to avoid blowing all the brigades up there. It is a clearly superior alternative with hindsight.



Out of interest, do you have an example of a viable alternative at Yorktown? If I've missed one previously I do apologize.

 

[1SGDan]

Since you have established yourself as the only arbiter of what is viable arguing with you about alternatives is a waste of time. However, imho there are several times when I think Mac missed opportunities. The two most obvious to me are:
-an Ernest effort at an early assault on the Warwick line
-a counterattack after Malvern Hill

 

[Saphroneth]

-an Ernest effort at an early assault on the Warwick line

Okay, thanks for that one - can you give me some more information on this? Do you mean on the 5th, on the 6th, or after the rainstorm (i.e. on the 10th at the earliest)? This helps define the strength of the enemy force.
I'm also assuming (unless you tell me otherwise) that you either mean an assault at the points of contact (on the 5th) or one all along the line (on the 6th or 10th).

-a counterattack after Malvern Hill

This one, on the other hand, has a much more obvious problem, elaborated on thus:

The fighting at Malvern Hill took place until 8:30 PM, which is effectively the end of the day (i.e. sunset/end of twilight) at that time of year - what this means is that a counterattack either takes place at night (which is frankly foolish) or that it takes place the next day, on the 2nd.

However, the 2nd is the fifth day in a row McClellan's army has been out of supply (those being the 28th, 29th, 30th, 1st and now 2nd) and attacking away from Malvern Hill means attacking away from the nearest viable base of supply (that being Harrisons Landing) and leaving it open to Lee's force to cut McClellan off, as he was historically planning.
An attack on the morning of the 2nd can easily be responded to by Lee having his right wing give ground to absorb pressure, thus:

(n.b. some of the Jackson force may actually be with the Magruder etc. force in practice. "Fresh" means not used in battle on the 1st by the Confederates). The likely position for Magruder to fall back to is probably to use Baily's Run as part of his right flank line.


while McClellan marches further away from his source of supply and Longstreet interposes himself to block that source of supply.

Essentially the problem is that the amy cannot feed itself on Malvern - the navy won't escort supplies past City Point - and by this point just about every formation has been in at least one big battle and are running low on ammunition as well as food. In the situation shown above (which only requires that McClellan's attack on the 2nd succeeds in driving Magruder back a mile or two) the AotP is on the far side of the Confederate army from their own supply base, and would have to withdraw back to the July 1 position just to free up the troops to attack Longstreet.

Even if McClellan succeeds completely and pushes Magruder's wing enough to make them fracture (no mean feat, it's 18 brigades counting Holmes and six of them are fully rested - that's comparable to half the Union army) then McClellan still doesn't have a supply of food or ammunition. He certainly can't break into Richmond like this...

So the fundamental problem with a post-Malvern counterattack is feeding and supplying the Union army.


ED: map correction. The fighting front marked as "Couch" and "Morell" was actually ten and a half brigades (Caldwell, Sickles, Meagher, Butterfield, Martindale, Griffin, Lovell, Buchanan, Weeden, Howe, half of Palmer) with Warren's brigade covering the bridge over the creek to the left of Malvern Hill proper and half of Palmer at the Turkey Island Creek bridge. The only reserve is McCall.

 

[1SGDan]

- concentrate necessary force at the best available location.
- armies do not exist to worry about food. An opportunity existed to attack a badly wounded enemy.

 

[Saphroneth]

- concentrate necessary force at the best available location.

That's for the attack on Yorktown, right? Do you at least know which day you're thinking of? It defines the strength of the enemy and how much intel McClellan could conceivably have.
For example, on the 5th McClellan ordered both of his wing commanders to attack as soon as they arrived, but both columns were smothered by artillery as they approached and his wing commanders balked at getting closer.
On the 6th McClellan has the rest of his force up but has had no time to recce the line so would have to basically just attack all along the line in hopes of a weak point.
On the 10th or later it is possible that a weak point could have been ID'ed (it actually took another several days to obtain and collate the info).

So the choices are:
5th - nothing, McClellan already ordered bayonet charges.
6th - attack all along the line with weak forces in the hope of finding a weak point.
10th or later - leave a screen along the rest of the line and concentrate disposable forces at a singular point.

- armies do not exist to worry about food. An opportunity existed to attack a badly wounded enemy.

Badly wounded is arguably false; Magruder had sent forwards only twelve brigades, with four unused and with up to fifteen more unused brigades in close support. He's got a marginally better ratio of fresh to used brigades than McClellan's north flank at Antietam on the afternoon of the 18th (4 fresh, 12 used for Magruder; 8 fresh, 25 used for McClellan after Couch arrives) in addition to having access to at least Ewell (3) and Holmes (2) as easy reinforcements. Magruder can't launch a further offensive on the 2nd, but he can hold a line reasonably well.

As for food, are you seriously asserting that the Army of the Potomac can exist without food?
If Longstreet gets to the indicated position (a movement he was planning to make and was in fact ordered to make, the movement only suspended because of a spontaneous attack at Malvern Hill) then the Army of the Potomac has no way to get food and will starve. Armies need to eat, which is why professionals study logistics (and they also need artillery ammunition to fight effectively, but a lot of batteries were low on ammo by the 1st).

 

[67th Tigers]

- concentrate necessary force at the best available location.

How does McClellan determine what this is? When? what are the chances of success? How much force is needed?

- armies do not exist to worry about food.

Armies that do not worry about food rapidly cease to exist. Those that don't worry about ammunition likewise.

An opportunity existed to attack a badly wounded enemy.

Yes, there is a wounded enemy, and you can attack. However, is that a good idea? You can't exploit any victory, because you've little ammunition and troops haven't eaten in days.

Also, what are the chances of success? A uphill frontal attack without artillery support against 24 brigades of infantry with strong artillery.

Porter reported he needed food and ammunition just to maintain his position.

 

[Saphroneth]

Also, what are the chances of success? A uphill frontal attack without artillery support against 24 brigades of infantry with strong artillery.

Just want to check the source of that 24 number - I assume that means the 16 of Magruder's main body, plus Holmes (2) and six from Jackson?

 

[67th Tigers]

Just want to check the source of that 24 number - I assume that means the 16 of Magruder's main body, plus Holmes (2) and six from Jackson?

Yes.

https://www.loc.gov/resource/g3884rm.gcw0652000/?sp=9&r=0.165,0.281,0.673,0.32,0

 

[Saphroneth]

Yes.

https://www.loc.gov/resource/g3884rm.gcw0652000/?sp=9&r=0.165,0.281,0.673,0.32,0

It's a pity maps like that aren't available for more actions.

 

[Saphroneth]

This is an attempt at a map which can be used to examine an attack on the 6th. Union positions are correct for the morning of the 6th, while Confederate positions include troops who arrived during the 6th. So the Union has some scope to redeploy before attacking on the 6th, but functionally this is going to mean six brigades on the right, 5-6 on the left and 4-5 in the centre.
No recce of the line has yet taken place.

Confederate strengths are all late April effectives only and do not include artillery (there's loads in Yorktown). They also do not include the 10th Georgia, which was screening the Confederate right.
Union strengths are roughly 2,500 inf effectives per brigade (this figure is approximate).
Green markings are the only places the Warwick can be crossed, the water is generally too deep to wade. Most of these have not yet been identified, indeed McClellan currently barely knows the course of the Warwick (his maps were wrong).
The marker for a crossing point at Wynns Mill (right) is the Upper Dam, which may or may not be crossable but is dominated from the ground on the far side.
The marker for a crossing point at Garrows is Dam Number One, which was crossable. Garrows Ridge is currently held by a Rebel outwork.
The marker for a crossing point down at Lees Mill (left) is an actual bridge, again dominated by the heights over it.
The positions of Cobb, Wilcox and Early are approximate as they were in reserve and there is no immediately obvious place to put them.

Any errors I've made, do point them out.


Given this it looks like there's nowhere the defences are weak enough to simply assault. Strong works were a huge force multiplier - the Stockade Redan saw a single regiment repel a corps, though in both cases that was 1863-period unit strength - and there's not really scope to gain artillery superiority to suppress the defences, as the defending artillery has works and will win a gun duel against field guns trying to deploy. (Each Union division has about 20 guns, which means the average Union brigade has roughly 1-2 batteries of 4 guns each. The heavy artillery reserve has another 100 guns but it's not feasible to bring the lot into action on the 6th.)

 

[Saphroneth]

So there are four options for attacking the Warwick line.

1) Attack straight off the line of march with both columns, stopping only long enough to deploy when you reach the defended area.
This was what McClellan attempted, and his corps commanders both refused to do so because of the strength of the line, unexpected terrain feature and artillery.

2) Attack on the 6th, bringing up the rest of the brigades.
Doing this second option functionally means moving Sykes' Regulars and the other three brigades with them, plus the 1-2 brigades spare on the left, and trying to find a good position to attack more or less by luck. There's enough brigades to form a two-deep line across most of the frontage (once they've linked up) but not to make it deeper, and unfortunately the more obvious of the two points to attack in the centre (the point with a track leading to it) is Wynns Mill. Garrow Ridge, which is somewhat weaker, is harder to identify and would have to be found by pure luck.
Thus an attack on the 6th would have to amount to orders to all DCs to "close up with the Warwick line, find somewhere which looks vulnerable, then charge". It means you couldn't expect more than a four-brigade attack at Wynns Mill and a two-brigade attack at Garrows, if the latter location is found at all, and the attacks would be made without much artillery support. At the same time six brigades go at Yorktown and the Redoubts, and four at Lees Mill.
This attack has very little chance of success and would essentially smash all of McClellan's brigades for nothing - strong permanent works atop a ca. 20 foot rise (depending on the work), with either a flooded river to deal with or heavy enfilade fire from Yorktown. Nowhere has the force ratio to overwhelm the defences and in some cases the attack is defiladed by the narrowness of the bridges/dams to cross.

3) Attack after the 10th, a recce'd attack with full support.
This is what McClellan was actually planning historically, landing his remaining troops (who hadn't been able to disembark until the 10th) and focusing on the point the engineers determined an attack was possible (information he got on the 14th). The attack was planned for the 16th or 17th (can't remember which), but the prep work got screwed up after McClellan left the day before and the brigade sent over to scout (against McClellan's instructions) collapsed the dam as they retreated.

4) Regular approaches.
Not an "early assault" so clearly not what you mean.

 

[rbasin]

It's a pity maps like that aren't available for more actions.

almost need a wall map. And more walls

 

[luinrina]

In To the Gates of Richmond Sears writes on p. 162:

These delusions* about the enemy invariably blinded McClellan to opportunity. When he told Mr. Lincoln his offensive awaited only the cooperation of earth and sky, he was in the midst of the longest period of good weather of the entire campaign. Between June 11 and June 23 it rained twice, briefly and lightly. Lee had but two men to his three, and only on June 16 did Lee send for Jackson and the Army of the Valley; only on the eighteenth did Jackson begin the long journey. Thus far in the campaign McClellan had not seized the slightest advantage from the fact that while Jackson's two divisions in the alley might be holding up reinforcements for the Potomac army, at the same time those two divisions were absent from the army defending Richmond. Nor did he act now.

* a) Pinkerton reported on June 15, "It is variously estimated that the Rebel army at Richmond and vicinity numbers from 150,000 to 200,000 men." Pinkerton afterward settled on a "general estimate" of 180,000, but cautioned that this was very probably an undercount.
b) Beauregard and a good part of his western army arriving in Richmond


My intention had been to find moments in the Peninsular Campaign where McClellan had alternatives and didn't use them properly. So when reading the above, I knew I needed to investigate whether McClellan really had an opportunity here or if Sears was mistaken. After everything I read about McClellan in other threads and seen in C-Span lectures, I was inclined to believe the latter though.

So, I started to break it down day by day.

According to Freeman's biography on Lee (vol. II, chapter 9, p. 95)

Rain came on the night of June 9 and continued through the 10th31 — a blessed downfall because it meant that the naturally hesitant McClellan would be chained to his positions for several days longer.

31 O. R., 11, part 1, p46; ibid., part 3, p224.

Not going to argue about the "naturally hesitant".


That meant that the roads would be quagmires and unusable for two to three days. Moving forward 2-3 days, I then saw that Stuart started for his ride around McClellan on the 12th – probably just when the roads were getting usable again. The encirclement of course caused some alarm in the Union army and probably hindered McClellan moving forward when he needed to ensure that there was no attack in his flank or rear. There were some reports that Stuart's cavalry was supported by infantry, after all. Until that crisis had passed, there was no thinking of an attack.

Stuart reached the Chickahominy on the 15th and found it still swollen from the recent rain. Even if the roads had by now dried and were usable again, a part of McClellan's army was stationed around the headwaters of White Oak Swamp – and if the Chickahominy was still swollen, the White Oak Swamp would surely be too.

Apart from that, McClellan's "delusions" would certainly stop every army commander from attacking. For one, McClellan's force on the Peninsula (five infantry corps) amounts to about 114,700, present for duty, equipped (June 20; OR 1 XI, pt. 3, p. 238). Pinkerton generally estimated 180,000 – roughly 3:2 for the Confederates. How was McClellan to know that there were fewer Confederates than the Union army numbered? In addition, McClellan believed Beauregard was in Richmond and brought a part of his western army with him to reinforce Lee's army.

Granted, he could have trusted Halleck when the latter said that Beauregard hadn't left Mississippi. But with all the differences going on on the political stage, I'd be vary of trusting intelligence coming from Washington too.

IMO it's easy to say that McClellan wasted an opportunity between the June 11 and June 23 – we have the advantage of hindsight; we know the numbers of both armies. But when putting myself in McClellan's position and going by what information he had and what was going on at that time, I believe he chose the prudent way not to attack between June 11 and June 23.

 

[Saphroneth]

Annoyingly I just lost quite a large post!

To summarize it in a simpler way:

Rain. McClellan stated in his report that it rained nearly every day until the 20th of June, and it should be noted that even if the roads were practical McClellan's operations to attack Richmond mandated bringing up heavy artillery onto high positions - he needed not just the roads but the area around the roads to be practical for moving artillery.

Troops (Confederate). McClellan tended to talk in terms of Present, not PFD, when discussing matters with others; in these terms, his prediction for "Richmond" was 150,000 (against the true value of 115,000), his prediction for "Jackson" was 30,000 (vice 25,000, the true value) and his prediction for "Beauregard" was 20,000 but he wasn't sure Beauregard's army was there. Note that the "true value" section for Richmond here is after Jackson got reinforced and so is lower than it was earlier on.
(Beauregard's force had dropped off the radar, and then Beauregard appeared in Richmond. The problem was that Beauregard had been replaced by Bragg and was in Richmond to argue his case!)

Troops (Union). McClellan's actual PFD strength with his army on 20 June was about 104,000 (Present this is 117,000) but 9,500 of the PFD (9,800 of the Present) had only just arrived within the last week - McCall unloaded 13-14 June and took a position in the line on the 19th, relieving Franklin's corps and allowing them to cross south of the river for offensive work. Using the 114,700 number means including Dix, who was garrisoning Fort Monroe and Norfolk.

Essentially, even in PFD terms the numbers around Richmond before McCall arrives are pretty much even (McClellan 94,500, Richmond as a whole 90,000). McCall gives McClellan enough slack to make an offensive concentration, but when Jackson comes down on his flank that falls apart.


Now, the ideal situation as far as McClellan (and the Union war effort) is concerned would be for McCall to have been accompanied by another division or two of McDowell's corps. This would have allowed McClellan to post these troops along the line of the Tolopatamoy and block Jackson, thus keeping the position secure and allowing his offensive concentration to grind forwards when the weather was clear.

Absent this, however, there's also the engineering prep work (specifically, digging in to resist attack). This is prudent and arguably necessary even in the true situation, as McClellan has to leave a big chunk of troops north of the Chickahominy but Lee can attack either side depending on which one is the weaker one. This was completed about 20 June.

So the question is really what an attack against Richmond actually looks like early on, because it looks like an attack by not much more than 60K Present against a city defended in toto by nearly twice that! The heavy guns really are essential to equalize things, and for that you need to wait until the ground dries and move deliberately.

Essentially the problem is that Lee kept Richmond well garrisoned.